Injector Bushing? Installation Question
 

I recently performed the Vacuum Hose Job From Hell - nearly every hose and solenoid snapped or crumbled upon removal no matter how gentle I tried to be.

In the process, I broke my oil metering lines because they were as brittle. In order to replace them, I had to pull both fuel rails but I did not remove the injectors from the rails.

I reused the rubber bushings? that were in the iron under the primary injectors and the thinner ones under the secondaries in the upper intake manifold. I plan to buy two of each next time and not cheap out. For the record, the old ones were still soft and pliable.

Needless to say, upon reassembly I have a huge vacuum leak. I can hear the air being sucked in the area of the injectors. The idle is way hugh and hunting. A spray of starting fluid in the injector area confirms that this is where the air leak is.

I have looked at the service manual but I'm not sure how the bushings are supposed to fit in the holes. Can someone help me?

The primaries seem to just fit in the hole and the injector assembly is just tightened down with the plastic insulator between the assembly and iron? The bushing is just placed in the recess on the iron and the seal is formed from the flat part of the injector pressing against the rubber? OR do I install the seal on the injector somehow?

As far as the secondaries - (where I really suspect the problem is...) I figured the thinner bushing was to be installed on the injector and then inserted into the lower intake manifold? I really think this is where I fucked up but not 100% sure.

Bottom line: I really (really) don't want to tear the engine down to the block a THIRD time if I fuck it up again. Is there a better digram available or assembly instructions available for these four bushings?

Thanks in advance.

Below I have red arrows pointing to the injector bushings in question (diagram only shows one for the primaries)


http://i9.photobucket.com/albums/a70...untitled-1.jpg

SO - what I am wondering, are the bushings for the injectors stretched around the injector or are they just placed in the recesses and then the fuel rail tightened creating a seal by compression?

The primary inj seals set on top of the center iron but not down in the hole. They seal the top of the inj to the top of the inj hole. Mazdas picture of them is wrong as they are different than the secondary seal which is what Mazda shown for them!

The secondary seals set inside the hole on top of the diffusers. The inj tip is then compressed against the seal. No wrapping around.

.

the seal was damaged on mine also and i replaced it with two injector orings works perfect actually has a little better seal. Take the good seal to a auto parts store and compare with the orings they have ..

Got the primaries right - they fit around the little tube inside the hole and the face of the injector presses down on top of them.

Now the secondaries ARE different and I am almost sure they are the ones leaking. So - do I put the seals inside the hole in the upper intake first and then tighten the fuel rail?

They just go in on top of the diffusers then you install the fuel rail. If you have a fuel leak, it's not from them.

^^ There isn't a fuel leak. I never removed the injectors from the rails - I removed the rails in one piece to access the MOP lines. I'm pretty sure the secondaries shouldn't be operating at idle anyway.

There IS a BIG ASS vacuum leak. I can hear it whooshing and the car hunts for idle continuously.

I am pretty sure its because I put the secondary seals on the injectors and installed them instead of putting them on the diffuser. They were thinner than the ones on the primaries so it looked like thats how they should have went.

TBH, I don't think there is a right or wrong way. As long as they are seated in the proper place, it doesn't matter how they got there.

This thread will answer all your questions.

https://www.rx7club.com/showthread.p...=injector+rail

You can make your own insulator/seal...
Good luck.
-Spence

I had the exact same thing happen, only I am an idiot.

Out of my frustration of trying to work in that mess they call the rats nest, I swapped the primary rail and secondary rail bolts... the secondary rail bolts are longer and don't allow the rail to sit all the way flush...

I am not saying you did what I did, but try wiggling the primary rail, if it moves, you did it.

BINGO!!!
I really help this helps someone else:

http://i9.photobucket.com/albums/a70...s/DSC05217.jpg

The bolts bottomed out. It didn't wiggle much but it DID leak - forcing me to strip the engine down again.

I probably never would have even checked it and just replaced the bushings if paulagre hadn't pointed out the bolts aren't interchangeable.

http://i9.photobucket.com/albums/a70...s/DSC05218.jpg

I like a root cause failure investigation like this one.....good eye !


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